I am a confused person trying to pour some concrete.
I think the question is Secondary level.

We are trying to pour some concrete
The area measures 26 ft long x 20 in wide. We want to pour the concrete 3 in thick.
One bag covers .41 cu. ft.
How many bags of concrete will we need to use?

Stephen La Rocque>


Hi Sue,

The bag states how much concrete it will produce in the units of cubic feet so you should first convert all your measurements to feet. There are 12 inches in a foot so

20 inches is 20/12 = 1.67 feet
and 3 inches is 3/12 = 0.25 feet

Thus the volume of concrete you need is

26 1.67 0.25 = 10.8 cubic feet.

One bag will produce 0.41 cubic feet so you need 10.8/0.41 = 26.3 bags. Hence you will need 27 bags.